The 33-year old was experiencing persistent hamstring towards the end of his English Premier League career, which finished with West Ham United, but since joining the Sounders he has not had a muscle injury.
Ljungberg puts it down to the fact that the Sounders found out exactly what the problem was and now he is enjoying an injury-free spell which could prolong his MLS career.
“I’m so thankful to Seattle that they found the problem. It was a fluke really. My hamstring broke and I went to see a famous surgeon over here for treatment,” he said.
“He said he’d seen similar things with ice hockey players so when the X-rays showed nothing wrong with my hamstrings, he asked if he could take a look at my hip.
“He thought I might have been playing for two or three years with a broken hip. At last I had an answer.
“I had surgery and came back with the same power. I haven’t had a muscle tear in two years.
“I’d given my word I’d stay in Seattle for two years and I was thankful to them for finding out what was wrong with my injury.<>
“The way I feel now feels great. I feel like I have another couple of good years left in me.”